And one-third to charles g



' 1,628,384 May 10 1927' s. w. MARVIN CLAMPING DEVICE FOR PRINTINGPLATES meta Dec. 9'. 1926 Fcgj.

Patented May 10, 1927.

`UNITED STATES Pa'rifnvr OFFICE.

SAMUEL W. MARVIN, 0F CAMBRIDGE, MASSA l-USETTS, ASSGNOR OF ONE-THRD TO`WILLIAM J'. MARSH, OF STOW, MASSACHUSETTS AND ONE-THIRDv T0 CHARLES G.

WELLS, OF BOSTON, MASSACHUSETTS.

` CLAMPING DEVICE FOR PRINTINGPLATES.

Application filed December .9, 1926. Serial No. 153,559.

`This invention relates to a clamp or gripping device for lise with thebed blocks of printing presses and is :in improvenn-:nt np- Aon theclamp or gripping device shown and .and locked by means of atool, and isof such construction as Will be described as to enable adjacent printingplates to be set closertogether for obtaining a narrow margin on theprinted sheet Without interfering with theoperation of the clampingdeviceby the tool. y l

. A further objectY lof the invention is to prevent backing olf of thecatch from the plate when the `tool is turned to lock the clampA to theblock. Y

These and `other features-of the invention Awill be pointed out in theclaims at the end yof this specification.

Fig. 1 is a plan of a bed block of a printing` press with two printingplates secured thereto by clamping` devices embodying' this -invention,one of said devices being shown in its unlocked.` position;

Fig. 2, a plan on a larger scale of a portion of the bed block and oneof the clamping;r devices; j

Fig'. 3, a side elevation of the clamping' device shown in Fig. 2,looking in the direction of the arrow thereon;

Fig'. 511. a cross section on the line fflv Fig. '3, and

Figs. 5 and 6, details on an enlarged scale to show the relation of theslots `in the meinbers of the clamping device in the unlocked and lockedpositions of the latter.

Referring` to the drawing, 10 represents the bed block of a printing,`press, and 12, 13 printing plates secured thereon bycla-mping devicesembodyingthe present invention.

The clamping devicesare provided with 'operating tool, such as ascrewdriver,

catches or members 14: adapted to engage the marginal portions of theprinting platesfin manner now comn'ionly practiced.A `rThe clampingdevices con'ipijise members l5, 16 having, their adjacent surfacesinclined, which operateas cam surfaces to cause the members to be movedlaterally with relation to `each other and into frictional engagementwith the opposed Walls 15%, 19 ofthe usual slots 2O in the bed block 10.i 7

. rihe catch @plate-engaging member 111 is lpivotally` secured to themember'157 and provisionis made for permittingthe member 1G to be madeof minimum length and have a maximum length-,of travel with relation tothe member 15. I

, To this end, the member 15 is provided at its opposite ends with boresor sockets' 28, 24. into which are extended stationary pins 25, 26secured to arms27, 28 on the meinber '16 at the opposite ends thereofand projecting inwardly therefrom (see Fig. 2);

The pins 25, 26 are secured to the arms 27, 2S with theirouteren'dsiiush or substantially flush with the outer surfaces of thearms, so that tWoor more of the clamping' devices may be placed intheslots 20 with their adjacent arms abutting, and thereby enable adjacentprinting plates to be secured on the bed. block and relatively Widelyseparated to obtain a relatively Wide margin on the printed sheet undersome conditions of use.

The clamping members 15, 16 are provided ivitli transverse slots 30, 81,which enable the clamping deviceto be moved in the slots 20 of the block10 toward and from a printing` plate thereon by ascreW-driver or liketool in the `hands of the operator. The slots 30, 3l' are designed toreceive au and by moving the tool bodily toward the printing plate, theclamping device is moved as a unit so'as to engage the catchA lei withthe printing plate. 'Y f lVhen thus positioned, the tool is presseddoivn on the bottom Wall 32 of the slot 30 in the catch-carrying member15 and is turned so Vasl to move tlie other member 16 towardthe'printing'plate and therebycause it to move the member laterally andwedge it between the member 16 and a side wall ot the slot 20 in the bedblock 10, thus securing the clamping plate to the bed block.

After one printing plate has been clamped to the block, an adjacentprinting plate as 13 is positioned by hand with relation to the clampedplate 12, and in practical operation 'frequent tine adjustments of theplates are necessary beforer they are. properly positioned on the block.

These adjustments require the locking and unlocking of the clampingdevices which cooperate with the plate being adjusted.

To enable the clamping devices to be unlocked by a tool after the plates'have been locked with their adj acent marginal edges in close proximityto each other and overlapping the opposite ends of the clamping device,the slot in the member 15 provided at its end adjacent the member 16,with an enlarged portion having beveled side walls 40, 41 which extendfrom approximatelyvv the center ot the slot 30 to the inclined sidethereof, which construction and arrangement provides a. space betweenone ot the side walls ot the slot 31 in the member 16, and one ot thebeveled sidewalls ot the slot 30 inthe member 15, for the entrance otthe screw-driver or other tool.

This is illustrated by the topmost clamping device located between theplates 12, 13, and in Fig. 5.

In Fig. 1, three clamping devices are represented asvco-operating withthe edge ot the plate 12 adjacent to the plate'13,vand are marked c, (l,and 6.

Another clamping device, marked f, is located between the devices c, (Z,and its catch engages the plate 13.

Gt' these clamping devices, c, (l and f are located between the plates12, 13, and their ends are overlapped by said plates. The clampingdevices (Z, are represented in their locked position while the device c'is represented as unlocked but with its catch 14 engaged with the plate12. j

It will be observed that the straight portion 43 of the rear wall ot theslot 30 is in the same plane as the 'front wall 44 of the slot 31 in themember 16, so that it. said straight wall 43 were continuedv tor thewidth et the member 15, it would cut ott the slot 30 from the slot 31,and thereb)T prevent the blade ot the screw-'driver being` entered intoboth slots.

By providing` the ba'eled side wall 40, a space is lett between it andthe` trent wall 44 ot the slot 31, (see Fig. 5), which is sufiicientlywide for the passage of the blade of the screw-driver into the slots 80,31, which enables the operator to turn the screw-driver or tool, so asto move the: member 16 lengthwise and into wedging position to' lock theclamping device to the bed block, in which position, the arm 27 isremoved from the member 15 as represented in the case ot the clampingdevices e and f.

The beveled wall functions also to permit the wedging member 16 to bemoved in the opposite direction by the operating` tool inserted into theslots 30, 31 in the locked position ofthe clamping device, as shown inFig. 6.

The plates 12, 16 in some cases require tine adjustments, which requireunlocking ot the clamping devices which co-operate with the plate beingadjusted and which are located between the plates.

For instance, assume that it is desired to unlock the clamp In thiscase, the operator inserts the tool into the slots 80, 31 and engagesthe straight portion 46 of the slot 30 with one end ot the blade and thewall ot the slet 81 with the other end o't'the blade and then turns thetool so as to move the member 16 rearwardly. (See Fig. 61') lt will beobserved that the beveled wall 40 in th is case permits the member 16to. be moved until the blade of the tool engages the beveled wall 40, atwhich time the clamping device is unlocked from the block and tree to bemoved in the slot 20su1iiciently to release the catch of the clampingdevice f' and permit the plate 13 toy bev adjusted.

The sockets 23, 24 in the wedge 'member l5 are ot larger diameter thanthe stationary pins 25, 26 to provide for lateral movement ot theAmember 15 when the co-operating` member 16 is moved into wedgingposition.

lit will be observed that the mounting of the member 15 on thestationary pins 25, 26 secured to the arms 2T, 28 ot the wedging member16 co-operates with the .enlarged end ot the slot 30 in the member 15,to enable the printing plates to be set in close proximity to each othertor narrow marginal purpeses and be locked and unlocked by means ot atool in the hands o1 the opera tor.

In practice, the operator inserts the clamping device in the slot in thebed block with the clamping device in condition to be freely movedlengthwise. in said slot, and he then places the screw-driver in theyslots and moves the clan'iping device as a unit toward the ing firmlyheld against the printing plate 1and of notlbeing disengaged or backedoff member 16 is made'deeperthan the slot 230'.

tool to engage the catch with the plate, the

tool engages only the bottom Wall of the slot 30. y

When the catch is engaged with the plate it will be held in firmengagement therewith by the operator pressing the catch member firmlyagainst the bottom of the slot 20 in the bed block.

While the catch member is thus held imthereon Without effecting movementof said vcatch member, and at the same time, effecting movement of theVWedge member into wedging or locking position.

This construction enables the operator to engage the catch with theplate and lock it in this position quickly and with one effort.

A preferred embodiment of the invention is herein shown, but it is notdesired to limit the invention to the particular construction shown.

Claims.

1. A clamping device of the character described, comprising a memberhaving an inclined inner surface and provided at its opposite ends witharms extended substantially at right angles from said inclined surfaceand having a transverse slot in its upper surface, stationary pinsattached to said arms with their outer ends substantially flush with theouter surfaces of said arms. a shorter co-operatiug member interposedbetween said arms and provided at its ends with sockets of largerdiameter than said pins and into which the latter are extended andhaving in its upper surface a transverse slot provided with a Wallhaving a straight portion and a beveled portion forming an enlargementof said slot at its end adjacent t-he inclined surface of said shortermember to leave a space for the entrance of an operating tool in thelocked position of said members, and a plate-engaging member carried bysaid shorter member.

2. A clamping device of the character described, Icomprising'eo-operating Wedgeshaped' members, oneofl which is longer than thevotherv and provided at its ends With arms entende-d substantially atright angles thereto and carrying stationary pins extended toward eachother, and the shorter member having end sockets of larger diameter thansaid pins yand into' which the latter are extended to support saidshorter member and permit movement of one member with relation to theother, said Wedge members having in their upper surfaces transversecooperating slots for the reception of an operating tool, the slot inthe shorter member being of greater Width at its inner end than the slotin the longer member and being of less depth than the slot inthe longermember. vil. A clampingr device ofthe character described, comprisingco-operating Wedgechlped members, one of which is longer than the otherand provided at its ends with arms cart-ended substantially at rightangles thereto and carrying stationaryV pins extended toward each other,and the shorter member having end sockets 0f larger' diameter than saidpins and into which the latter are extended to support said shortermember' and permit movement of one member with relation to the other,said wedge members having; in their upper surfaces transverse c0-operating slots for the reception of an operating tool, the slot in theshorter member having` one Wall thereof providedy With a straightportion and Witha beveled portion extended away from the inner end ofsaid straight portion to enlarge the end of the slot adjacent the longermember and provide a space for the insertion of the .operating tool intoboth slots with the straight portion of the slot in the shorter memberlsubstantially in the plane of a Wall of the slot in the longer memberwhen the said Wedge members are in their locked position.

4. A clamping device of the character described, comprising Wedge-shapedmembers of unequal length and connected together' to be moved as a unitand to be moved individually with relation to each other, said Wedgemembers having in their upper surfaces transverse cri-operating slotsfor the reception of an operating tool. the slot in the shorter memberbeing of greater Width at its end adjacent the slot in the longer memberto provide a space for the insertion of an operating tool into bothslots when said members are in their locked position.

5. A clamping device of the character described, comprising Wedge-shapedmembers of unequal length and connected together to be moved as a unitand to be moved individually with relation to each other, said Wedgemembers having in their upper surfaces transverse co-operating slots forthe reception of an operating tool, the slot in the 1 shorter memberbeing of greater Width at its end adjacent the slot in the longer memberto provide a space for the insertion of an operating tool intoV bothslots When the Wedge members are in their looked position, and the slotin the longer-member being of greater depth than the slot in the shortermember to enable the operating tool to engage the bottom, Wall of theslot in the shorter member and be turned thereon to move the longermember in one direction Without moving the shorter member in theopposite direction. V

In testimony whereof, I have signed my name to this specification.

SAMUEL 7. MARVIN.

